title: Temperature and magnetic field dependence of a Kondo system in the weak coupling regime.
abstract: The Kondo effect arises due to the interaction between a localized spin and the electrons of a surrounding host. Studies of individual magnetic impurities by scanning tunneling spectroscopy have renewed interest in Kondo physics; however, a quantitative comparison with theoretical predictions remained challenging. Here we show that the zero-bias anomaly detected on an organic radical weakly coupled to a Au (111) surface can be described with astonishing agreement by perturbation theory as originally developed by Kondo 60 years ago. Our results demonstrate that Kondo physics can only be fully conceived by studying both temperature and magnetic field dependence of the resonance. The identification of a spin 1/2 Kondo system is of relevance not only as a benchmark for predictions for Kondo physics but also for correlated electron materials in general.
authors.affiliation: Max-Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany.
authors.forename: Yong-hui
authors.initials: YH
authors.lastname: Zhang
authors.forename: Steffen
authors.initials: S
authors.lastname: Kahle
authors.forename: Tobias
authors.initials: T
authors.lastname: Herden
authors.forename: Christophe
authors.initials: C
authors.lastname: Stroh
authors.forename: Marcel
authors.initials: M
authors.lastname: Mayor
authors.forename: Uta
authors.initials: U
authors.lastname: Schlickum
authors.forename: Markus
authors.initials: M
authors.lastname: Ternes
authors.forename: Peter
authors.initials: P
authors.lastname: Wahl
authors.forename: Klaus
authors.initials: K
authors.lastname: Kern